Multi-code, tamper proof, card-operable magnetic locking mechanism

ABSTRACT

A programmable, card-operable magnetic locking mechanism of the type having a movable tumbler-carrying core disposed above a fixed keeper plate provided with openings which normally receive the ends of tumbler magnets in the core to prevent movement of the core, some of the tumbler magnets being movable out of the keeper plate openings by a magnetically coded program card inserted into a slot above the core, and the remainder of the tumbler magnets being movable by a magnetically coded pass card inserted into a slot beneath the keeper plate. The program cards and the pass cards are coded with magnetized spots arranged to align with the tumbler magnets when the cards are inserted into their respective slots. The tumbler-receiving openings in the keeper plate are of two different sizes. If one of the tumblers extends into one of the smaller openings, the core cannot be moved. If none of the tumblers extends into a smaller opening, but one of the tumblers extends into one or more of the larger openings, the core can be moved a limited distance to actuate a first switch. If none of the tumblers extend into the keeper plate openings, the core can be moved through an extended distance to actuate a second switch. A control circuit which includes both switches is provided with a control switch for selectively rendering the first switch effective or ineffective to actuate an operator (e. g., a turnstile, parking gate, etc). A tamper-prevention pin is slidably mounted in an opening in the core so that if tumblers are displaced from their respective openings in the keeper plate by some unauthorized means (e. g., by sharply striking the lock from above, or by turning the lock upside down), the tamper-prevention pin will move into engagement with a fixed structure in the lock to prevent movement of the core.

nited States Patent Sedley I54] MULTl-CODE, TAMPER PROOF,

CARD-OPERABLE MAGNETIC Primary Examiner-Albert G. Craig Jr. Attorney-Paul L. Gardner and Kendrick, Subkow and Kriegel [57] ABSTRACT A programmable, card-operable magnetic locking [4s] Dec. 5, 1972 mechanism of the type having a movable tumbler carrying core disposed above a fixed keeper. plate provided with openings which normally receive the ends of tumbler magnets in the core to prevent movement of the core, some of the tumbler magnets being movable out of the keeper plate openings by a magnetically coded program card inserted into a slot above the core, and the remainder of the tumbler magnets being movable by a magnetically coded pass card inserted into a slot beneath the keeper-plate. The program cards and the pass cards are coded with magnetized spots arranged to align with the tumbler magnets when the cards are inserted into their respective slots. The tumbler-receiving openings in the keeper plate are of two different sizes. If one of the tumblers extends into one of the smaller openings, the core cannot be moved. If none of the tumblers extends into a smaller opening, but one of the tumblers extends into one or more of the larger openings, the core can be moved a limited distance to actuate a first switch. If none of the tumblers extend into the keeper plate openings, the core can be moved through an extended distance to actuate a second switch. A control circuit which includes both switches is provided with a control switch for selectively rendering the first switch effective or ineffective to actuate an operator (e. g., a turnstile, parking gate, etc).

A tamper-prevention pin is slidably mounted in an opening in the coreso that if tumblers are displaced from their respective openings in the keeper plate by some unauthorized means (e. g., by sharply striking the lock from above, or by turning the lock upside down), the tamper-prevention pin will move into engagement with a fixed structure in the lock to prevent movement of the core.

Claims, 6 Drawing Figures PATENTEDnEc 5 I972 SHEET 2 BF 2 .V o 0 o INVENTOR 52066 .9. semey The present invention relates to locks of the type having magnetic locking tumblers adapted to be displaced by a magnetically coded card.

Card-operable magnetic locks, such as those disclosed in U.S. Pat. Nos. 2,648,729 and 3,444,71 l, have been widely used for operating barriers (e. g., parking lot gates, turnstiles, doors, etc.) in various types of access control systems. Such a lock typically comprises a core which carries a plurality of magnetic tumbler pins arranged in a predetermined pattern, and a keeper plate which is providedwith a plurality of openings for receiving the ends of the tumbler pins. The ends of all or some of the tumbler pins are normally biased into some of the keeper plate openings to prevent relative movement between the core and the keeper plate. When a magnetically coded pass card (i. e., a card having magnetic areas or elements arranged in a pattern corresponding to the pattern of the tumbler pins which extend into the keeper plate openings) is inserted into the lock, it displaces the tumbler pins from the openings in the keeper plate and moves the core or the keeper plate to actuate a switch, open a barrier and permit access to a restricted area (e. g., p'arking lot, convention center, industrial plant, private club, etc.).

As shown in U.S. Pat. No. 3,444,711, one or more of the magnetic tumbler pins may be biased into the keeper plate openings by inserting a program card into the lock. The program card is provided with a pattern of magnetized areas or spots arranged to align with and displace one or more of the tumbler pins when inserted into the lock, and the pass cards for opening the lock are magnetically coded to displace those tumbler pins which are biased into the keeper plate openings by the program card. The pattern or combination of the tumbler pins which extend into the keeper plate openings may be changed by simply inserting a new program card (i. e., one having a different pattern of magnetized spots) into the lock, thereby rendering the old pass cards (i. e., those corresponding to the old program card) ineffective to displace all of the pins and open the lock. Since the combination or pro gram of the lock can be so readily changed, the lock is termed a programmable lock.

While programmable locks of the type shown in U.S. Pat. No. 3,444,711 have proven to be highly effective in use and commercially successful in the market place, there has arisen a need for such a lock whose combination may be quickly and simply changed without opening the housing of the lock and changing the program card." Such a lock may be particularly useful, for example, in access control systems for restricted areas (e. g., buildings or parking lots) where different groups (e. g., day students and night students, or day shift workers and night shift workers) are to be permitted access during limited periods of each day and denied access during other periods.

The lock of the present invention fulfills such a need by providing a lock having manually operable or automatically operable switch means for quickly and easily rendering the lock operable or inoperable by cards magnetically coded in a particular pattern.

The lock of the present invention also includes tamper-prevention means for preventing opening of the lock without a properly coded pass card.

Other objects, features and advantages of the present invention will become apparent from the following detailed description and the accompanying drawings of a preferred embodiment.

IN THE DRAWINGS FIG. 1 is a top plan view of a dual code, tamper proof lock constructed in accordance with the teachings of the present invention.

FIG. 2 is a sectional side elevation taken along the line 2-2 of FIG. 1.

FIG. 3 is a sectional side elevation similar to FIG. 2.

FIG. 4 is a sectional side elevation similar to FIGS. 2 and 3.

FIG. 5 is a schematic diagram of a circuit which may be used in conjunction with the lock shown in FIGS.

FIG. 6 is an exploded perspective view of the lock shown in FIGS. 14.

DESCRIPTION OF A PREFERRED EMBODIMENT The lock 10 shown in the drawings comprises atop plate 12, a pair of laterally-spaced program card guide bars l4, 14, a card retaining plate 16, a pair of laterally spaced core guide bars 18, 18, a keeper plate 20, a bottom plate 22 and a pair of laterally spaced pass card guide rails 24, 24, all held together in vertically stacked relationship by four bolts 26, lock washers 28 and nuts 30 (FIG. 6).

The laterally spaced core guide bars 18, 18 define a slot between the card retaining plate 16 and the keeper plate 20 for slidably receiving a generally flat core member 32.

The core member 32 is provided with a matrix of transversely extending holes 34, some of which carry magnetic tumblers 36. The tumblers 36 are generally cylindrical in shape and are slidably disposed in their respective holes 34 in the core 32 for transverse sliding movement (i. e., up and down movement).

A hole 38 is provided in the core 32 for receiving an upwardly extending spacer pin 40 mounted on the keeper plate 20, and a stepped opening 42 is provided for slidably receiving a stepped tamper-prevention pin 44 (FIGS. 2, 3, and 4).

An actuator post 46 is mounted on the slidable core 32 and extends upwardly through elongated, vertically aligned slots 48, 50 in the card retaining plate 16 and the top plate 12, respectively. A compression spring 51 is connected between the actuator post 46 and the forward end of the card retaining plate 16 for urging the actuator post 46 and the core 32 to their retracted position at the forward end (the left end as viewed in the drawings) of the lock 10.

A pair of microswitches 52 and 54 having leaf spring type operator arms 56 and 58, respectively, are mounted on the top plate 12 behind the slot 50. The arms 56 and 58 extend over the rear portion of the slot 50 and are adapted to be engaged by the actuator post 46 as the slidable core 32 moves rearwardly (toward the right as viewed in FIGS. 2, 3, 4, and 6). As best shown in FIG. 6, the arm 56 of switch 52 is disposed forwardly of the arm 58 so that the switch 52 will be closed first (before switch 54) as the actuator post 46 moves rearwardly.

The keeper plate 20 is provided with a matrix of smaller holes 60 and larger holes 62 which are in substantial vertical alignment with the holes 34 in the slidable core 32 when the core is in its retracted position (the position shown in FIG. 2). As best shown in FIG. 2, gravity normally maintains the lower ends of the tumbler pins 36 in the keeper plate holes 60 and 62. The rear edges of the holes 60 and 62 serve as abutment edges which engage the tumbler pins 36 to prevent or limit rearward movement of the core. The bottom plate 22 prevents the tumbler pins 36 from dropping through the keeper plate holes.

From the foregoing it will be appreciated that when one or more of the magnetic tumblers 36 extends into one of the smaller holes 60-of the keeper plate 20, the core 32 cannot be moved rearwardly from its retracted position (FIG. 2 position). When none of the tumblers extend into the smaller holes 60, but one or more tumblers extends into one of the larger keeper plate holes 62, the core 32 can be moved rearwardly (to the right as shown in the drawings) a limited distance, to an intermediate position (FIG. 3). When none of the tumblers 36 extend into the keeper plate holes 60 and 62, the core may be moved rearwardly to its fully extended position (FIG. 4).

The leaf arms 56 and 58 of the switches 52 and 54, respectively, are so positioned that when the core 32 is moved to its intermediate position (FIG. 3), the actuator post 46 mounted thereon will engage leaf arm 56 and close switch 52, and as the core 32 is moved further rearwardly to its fully extended position (FIG. 4) the actuator post 46 will engage the operator arm 58 and close the switch 54.

The tumbler pins 36 may be moved upwardly, out of their associated holes 60 and 62 in keeper plate 20, by inserting a magnetically coded pass card into the lock 10. The laterally spaced pass card guide rails 24, 24 are stepped, as at 76, to define a pass card receiving slot 78 beneath the bottom plate 22, and the upper forward edges 80 of the rails are curved outwardly at their forward ends 80 to facilitate insertion ofa pass card.

Since the pass card receiving slot 78 is disposed at the bottom of the unit and has an open bottom, any foreign matter (e. g., sticks, coins, etc.) inserted into the slot 78 will dropthrough the slot and will not interfere with operation of the unit.

A properly coded pass card (i. e., one that will operate the lock 10) is one having magnetized areas or spots 84 arranged to underlie the tumbler pins 36 when the car is inserted into the slot 78 and polarized to repel the pins 36 out of the keeper plate holes. If the pass card inserted into the slot 78 has magnetized spots 84 underlying all of the tumbler pins 36 (e. g., daynight pass card 82', FIGS. 4 and 6), all of the pins will be repelled upwardly out of the keeper plate holes 60 and 62, thereby permitting movement of the core 32 to its fully extended position (FIG. 4), wherein the actuator post 46 closes both switches 52 and 54. If the pass card only has magnetized spots 84 underlying only those pins 36 in the smaller keeper plate holes 60 (e. g., night pass card 82, FIGS. 3 and 6), one or more of the tumbler pins 36 will extend into one or more of the larger keeper plate holes, thereby permitting only limited movement of the core; i. e., to its intermediate position (FIG. 3) wherein the actuator post 46 closes only the bottom switch 52.

plate 12 and the retaining plate 16 for receiving a program card 68. The rear ends 70, of the program card guide bars 14, 14 and the lower rear edge of the top plate 12 are bevelled to facilitate insertion of the program card 68 and the forward end of the card retaining plate 16 is turned upwardly to provide a stop flange 71 which limits forward movement of a program card inserted into the slot 66. The rear portion of the plate 16 is bowed upwardly at 73 to retain the program card in the slot 66.

The program card 68 is provided with magnetized spots 69 which are so positioned and polarized to attract selected tumbler pins 36 out of their associated holes 60 and 62 in the keeper plate 20. An elongate slot 72 is provided in the forward end of the program card 68 to receive the actuator post 46 and prevent interference with forward and rearward movement thereof.

The program set card 68 and the pass card 82 are preferably of the type shown and described in US. Pat. Nos. 3,444,711 and No. 3,611,763. Such cards typically comprise a sheet of rubber or plastic binder material having ferromagnetic particles suspended and substantially evenly distributed therein. The magnetic spots 69 and 84 are provided by magnetizing selected discrete portions of the cards transversely through the thickness thereof. The use of such a pass card, as opposed to a shim typepass card (of the type shown, for example, in US. Pat. No. 2,595,769), permits the slot 78 to be located at the bottom of the unit 10 since the magnetized spots 84 can repel the tumbler pins 36 upwardly.

for the sake of clarity the directions of polarization of the magnetic tumbler pins 36 and the magnetic spots 69 and 84 on the cards 68 and 82 have not been illustrated in the drawings. It will be appreciated, of course, that the directions of polarization of the magnetic pins 36 may be varied, so long as the magnetic spots on the program card and the properly coded pass cards are correspondingly varied so as to repel all of the pins 36 out of their associated holes 60 and 62 in the keeper plate 20. Reference may be had to US. For No. 3,595,042 for a description of how the magnetic pins may be polarized.

A tamper-prevention pin 44 is provided in an opening 42 in the core 32 for preventing unlocking of the unit 10 by unauthorized persons (i. e., persons who have not been issued properly coded pass cards). In the absence of such tamper prevention means, a sharp blow struck on the top of the unit 10 (if the top is accessible) would cause the magnetic tumbler pins 36 to jump upwardly out of the holes 60 and 62 in the keeper plate 20, thereby permitting a card-like object inserted at the proper instant to push the core 32 rearwardly and actuate the switches 40 and 42. Moreover, if the unit 10 is not securely bolted or otherwise secured in an upright position, the unit could be unlocked by turning it upside-down, whereupon the pins 36 would drop out of the keeper plate holes.

The tamper-prevention pin 44 is provided with a circumferentially enlarged flange 44a at its lower end, and the opening 42 in which the pin is disposed is provided with an inwardly extending flange 42a at the upper end. If the lock is struck with a sharp blow or turnecl-upside-down so as to move the tumbler pins 36 out of their associated openings 60 and 62 in the keeper plate 20, the tamper-prevention pin 44 will also move upwardly so that the upper end thereof extends into the rear portions of the slot 48 in the card retaining plate 16. (see phantom line position of tamper-prevention pin 44 in FIG. 2). The presence of the upper end of the pin 44 in the slot 48. prevents significant rearward movement of the core 32, thereby preventing actuation of the switches 52 and 54. The lower flange 44a on the pin 44 and the upper flange 42a in the pin-receiving hole 42 prevent the pin 44 from jumping out of the hole 42.

The tamper-prevention pin 44 is preferably made of a non-magnetic material (e. g., brass) which will not influence or be influenced by the magnetic fields of the magnetic tumbler pins 36.

FIG. 5 schematically illustrates a circuit 100 which may be employed in conjunction with the locking mechanism 10. The circuit 100 includes the switches 52 and 54, an operator 104 (e. g., for operating a parking gate), and a manually operable or automatically operable (e. g., by a time clock) control switch 102 for selectively connecting the switch 52 to the operator 104. It will be noted that when the control switch 102 is open (solid line position in FIG. 5) the second or upper switch 54 must be closed to complete the circuit and actuate the operator 104; When the control switch 102 is closed, however, the first or bottom switch 52 will also actuate the operator 104.

In use, the locking mechanism 10 is installed at the entrance to a restricted area, such as a parking lot, and the operator 104 (FIG. 5) is operatively connected to an entry barrier (not shown), such as a parking gate.

A program set card 68 is inserted into the receiving slot 66 between the top plate 12 and the card retaining plate 16 to attract one or more of the tumbler pins 36 out of their associated holes 60 and 62 in the keeper plate 20. The stop flange 71 on the forward end of the card retaining plate 16 will prevent the program card 68 from being pushed too far forwardly, and the upwardly bowed portion 73 will releasably retain the program card in place.

Properly coded pass cards 82 and 82' may then be distributed to those persons who are to have access to the restricted area. Since the pass card 82 will only open the lock 10 if the control switch 102 (FIG. 5) is closed, these cards shouldbe issued to those persons who are to be permitted entry only during a specific time period (e. g., at night).

The other pass card 82' is coded to repel all of the locking pins 36 from the keeper plate openings 60 and 62 and will actuate both microswitches 52 and 54 to operate the entry barrier (not shown), whether the control switch 102 is open or closed. Accordingly, these cards should be issued to persons who are to be permitted access at any time.

Of course, the pass cards 82 and 82' should be coded so that they will repel those tumbler pins 36 which are not attracted by the program card 68. If no program card 68 is present in the slot 66, the pass card must have magnetic spots to repel all of the required pins 36.

When a night pass card 82 is inserted into the pass card'receiving slot 78 (FIG. 3), the magnetic spots" 84 thereon will repel those pins 36 which extend into the smaller keeper plate holes 60, and further movement of thecard 82 into the slot 78 will push the core flange 85 and core 32 rearwardly a limited distance until the pins 36 extending into the larger keeper plate holes 62 engage the rear edges of those holes. When the core 32 is moved to this intermediate position the actuator post 46 will engage the leaf spring arm 56 andclose the lower switch 52, but the switch 54 will remain open and the operator 104 will not be actuated unless the control switch 102 is closed.

Thus, at any time it is desired to permit access by persons holding night pass cards 82, it is only necessary to close the control switch 102, and when it is desired to render such night pass cards 82 ineffective to actuate the operator 104 and open the entry barrier (not shown), itis only necessary to open the control switch 102. It is contemplated that the control switch 102 may be manually operable (e. g., by a suitable key) or automatically operable (e. g., by a time clock).

The day-night pass card 82 is provided with magnetized spots 84 and 84' which will repel all of the locking pins 36 out of the keeper plate holes 60 and 62 so that the pass card 82 may push the core 32 rearwardly to its fully extended position (FIG. 4) wherein the actuator post closes both of the switches 52 and 54. Thus, the day-night pass card 82' will actuate the operator 104 whether the control switch is open (e. g., during the day) or closed (e. g., at night).

Of course, numerous modifications may be made to the locking unit 10 illustrated in the drawings and described herein without departing from the spirit and scope of this invention. For example, while the preferred embodiment disclosed in the drawings and described above is adapted to be unlocked atdifferent times by cards having two different codes thereon, it is, of course, contemplated that the unit may be designed to be operated by cards having any number of different codes, simply by providing additional, progressively larger sets of openings in the keeper plate and additional microswitches. Accordingly, it is intended that the present invention be limited only by the scope of the appended claims.

I claim:

1. A magnetic lock comprising: a tumbler-carrying member and a keeper member disposed adjacent to one another with one of said members being disposed below the other of said members; means defining a keyreceiving opening below the lower of said tumbler-carrying member and said keeper member; at least two magnetically responsive tumblers movably disposed in said tumbler-carrying member; first abutment means carried by said keeper member for engaging a portion of one of said tumblers to prevent substantial relative movement between said tumbler-carrying member and said keeper member; second abutment means carried by said keeper member for engaging a portion of the other of said tumblers to prevent extended relative movement between said tumbler-carrying member and said keeper member; said one tumbler being normally biased into a locking position wherein it engages said first abutment means on said keeper member when relative movement between said tumbler-carrying member and said keeper member is created; said other tumbler being normally biased into a locking position wherein it engages said second abutment means on said keeper member when relative movement between said tumbler-carrying member and said keeper member is created; each of said tumblers being movable out of its said locking position by the magnetic field set up between said tumbler and a magnetically responsive portion of a key inserted into said key-receiving opening; means for creating limited relative movement between said tumbler-carrying member and said keeper member when said one tumbler is out of its said locking position and said other tumbler is in its said locking position and for creating extended relative movement between said members when both of said tumblers are out of their said locking positions.

2. A magnetic lock according to claim 1, and further comprising control circuit means for actuating operator means; said control circuit means comprising first switch means operable in response to limited relative movement between said tumbler-carrying member and said keeper member; control switch means for selectively rendering actuation of said first switch means effective to actuate operator means; and second switch means operable in response to extended relative movement between said members for actuating operator means.

3. A magnetic lock according to claim 1, and further comprising a third magnetically responsive tumbler movably disposed in said tumbler-carrying member; third abutment means carried by said keeper member for engaging a portion of said third tumbler; said third tumbler being normally biased into a locking position wherein it engages said third abutment means; and means defining a program member receiving opening in said lock for receiving a program member having a magnetically responsive portion adapted to move said third tumbler out ofits said locking position.

4. A magnetic lock according to claim 1, and further comprising spring means normally maintaining said tumbler carrying member and said keeper member in a locking position, relative to one another, wherein each of said tumblers is disposed in its said locking position.

5. A magnetic lock according to claim 1, and further comprising a tamper-prevention member operative in response to a non-magnetic force moving said tumblers out of their said locking positions to prevent substantial relative movement between said tumbler-carrying member and said keeper member.

6. A magnetic lock according to claim 1, wherein said tumbler member and said keeper member are generally planar members disposed adjacent to one another, and each of said magnetically responsive tumblers is a generally elongated, cylindrical member slidably disposed in said tumbler carrying member for movement in a direction generally along the axis of the tumbler; and further comprising a plurality of openings in said keeper member; each of said openings being adapted to receive the end portion of one of said cylindrical tumblers; one of said openings in said keeper member being larger than the other of said openings; said first abutment means comprising a portion of the peripheral edge of said smaller opening in said keeper member and said second abutment means comprising a portion of the peripheral edge of said larger opening in said keeper member.

7. A magnetic lock according to claim 6, wherein each of said generally cylindrical tumbler members is magnetically polarized along its length.

8. A magnetic lock according to claim 6, wherein said key-receiving opening comprises means defining a card-receiving slot having a forward end into which a card-shaped key is adapted to be inserted, and an open rear end; and wherein said means for creating movement between said tumbler-carrying member and said keeper member comprises flange means connected to one of said tumbler-carrying member of said keeper member; said flange means overlying said open rear end of said key-receiving slot and being adapted to be engaged by a card-shaped key inserted into said slot.

9. A magnetic lock according to claim 6, wherein said tumbler-carrying member is disposed above said keeper member, and said tumblers are normally maintained in their said locking positions by gravity.

10. A magnetic lock according to claim 9, wherein said tumbler-carrying member is movable relative to said keeper member, and said flange means comprises a flange connected to said tumbler member; and further comprising first and second switch means and actuator means carried by said tumbler member for sequentially actuating said first and second switch means as said tumbler member is moved rearwardly relative to said keeper member.

11. A magnetic lock according to claim 6, wherein said tumbler-carrying member is movable relative to said keeper member, and further comprising spring means normally biasing said tumbler member to a retracted position wherein each of said magnetically responsive tumblers has one of its ends disposed in one of said keeper member openings. I

12. A magnetic lock according to claim 6, wherein said tumbler-carrying member is movable relative to said keeper member, and further comprising a nonmagnetic tamper-prevention member slidably disposed in said tumbler-carrying member, and fixed means disposed above and adjacent to said tamper-prevention member; whereby when said tumblers are moved upwardly out of their locking positions by a non-magnetic force said tamper-prevention member will be moved upwardly and will engage said fixed means when said tumbler-carrying member is moved rearwardly, thereby preventing substantial rearward movement of said tumbler-carrying member.

13. A magnetic lock comprising: a tumbler-carrying member; a keeper member disposed adjacent to said tumbler-carrying member; means defining a keyreceiving opening in said lock; at least two magnetized tumblers movably disposed in said tumbler-carrying member; first abutment means carried by said keeper member for engaging a portion of one of said tumblers to prevent substantial relative movement between said tumbler-carrying member and said keeper member; second abutment means carried by said keeper member for engaging a portion of the other of said tumblers to prevent extended relative movement between said tumbler-carrying member and said keeper member; said one tumbler being normally biased into a locking position wherein it engages said first abutment means on said keeper member when relative movement between said tumbler-carrying member and said keeper member is created; said other tumbler being normally biased into a locking position wherein it engages said second abutment means on said keeper member when relative movement between said turnbler-carrying member and said keeper member is created; each of said tumblers being movable out of its said locking position by the magnetic field set up between ,said tumbler and a magnetized portion of a magneticallycoded key member inserted into said keyreceiving opening; means for creating limited relative I movement between said tumbler-carrying member and said keeper member when said one tumbler is out of its said locking position and said other tumbler is in its said locking position and for creating extended relative movement between said members when both of said tumblers are out of their said locking positions.

14. A magnetic lock according to claim 13, and further comprising control circuit means for actuating operator means; said control circuitmeans comprising first switch means operable in response to limited relative movement between said tumbler-carrying member and said keeper member; control switch means for selectively rendering actuation of said first switch means effective to actuate operator means; and second switch means operable in response to extended relative drical tumblers; one of said openings in said keeper member being larger than the other of said openings; said first abutment means comprising a portion of the peripheral edge of said smaller opening in said keeper member and said second abutment means comprising a portion of the peripheral edge of said larger opening in said keeper member.

19. A magnetic lock according to claim 18, wherein each of said generally cylindrical tumbler members is magnetically polarized along its length.

20. A magnetic lock according to claim 18, wherein said key-receiving opening comprises means defining a card-receiving slot having a forward end into which a card-shaped key is adapted to be inserted, and an open rear end; and wherein said means for creating movement between said tumbler-carrying member and said keeper member comprises flange means connected to said tumbler-carrying member is disposed above said movement between said members for actuating operator means.

15. A magnetic lock according to claim 13, and

' further comprising a third magnetized tumbler movably disposed in said tumbler-carrying'member; third abutment means carried by said keeper member for engaging a portion of said third tumbler; said third tumbler being normally biased into'a locking position wherein it engages said third abutment means; and means defining a program member receiving opening in said lock for receiving a program member having a magnetically responsive portion adapted to move said third tumbler out of its said locking position.

16. A magnetic lock according to claim 13, and further comprising spring means normally maintaining said tumbler-carrying member and said keeper member in a locking position, relative to one another, wherein each of said tumblers is disposed in its said locking position.

17. A magnetic lock according to claim 13, and further comprising a tamper-prevention member operative in response to a non-'magnetic'force moving said tumblers out of their said locking positions to prevent substantial relative movement between said tumbler-carrying member and said keeper member.

18. A magnetic lock according to claim 13, wherein said tumbler member and said keeper member are generally planar members disposed adjacent to one another, and each of said magnetically responsive tumblers is a generally elongated, cylindrical member slidably disposed in said tumbler carrying member for movement in a direction generally along the axis'of the tumbler; and further comprising a plurality of openings in said keeper member; each of said openings being adapted to receive the end portion of one of said cylinkeeper member, and said tumblers are normally maintained in their said locking positions by gravity.

22. A magnetic lock according to claim .21, wherein said tumbler-carrying member is movable relative to said keeper member, and said flange means comprises a flange connected to said tumblercarrying member; and further comprising first and second switch means and actuator means carried by said tumbler-carrying member for sequentially actuating said first and second switch means as said tumbler-carrying member is moved rearwardly relative to said keeper member.

23. A magnetic lock according to claim 18, wherein said tumbler-carrying member is movable relative to said keeper member, and further comprising spring means normally biasing said tumbler-carrying member to a retracted position wherein each of said magnetically responsive tumblers has one of its ends disposed in one of said keeper member openings.

24. A magnetic lock according to claim 18, wherein said tumbler-carrying member ismovable relative to said keeper member, and further comprising a tamperprevention member slidably disposed in said tumblercarrying member, and fixed means disposed above and adjacent to said tamper-prevention member; whereby when said tumblers are moved upwardly out of their locking positions by a non-magnetic force said tamperprevention member will be moved upwardly and will engage said fixed means when said tumbler-carrying member is moved rearwardly, thereby preventing substantial rearward movement of said tumbler-carrying member.

25. A magnetic lock comprising: a generally planar tumbler-carrying member having a plurality of magnetic tumblers slidably mounted therein for transverse movement across the thickness of said member; a generally planar keeper member disposed adjacent to and substantially parallel to said tumbler carrying member; means defining a plurality of openings in said keeper member for receiving portions of said tumblers to prevent or limit relative sliding movement between said tumbler-carrying member and said keeper member; said openings in said keeper member including at least one smaller opening adapted to receive a portion of one of said magnetic tumblers in said tumbler-carrying member to prevent substantial relative movement between said tumbler-carrying member sand said keeper member, and at least one larger opening adapted to receive a portion of the other of said magnetic tumblers to prevent extended relative movement between said tumbler carrying member and said keeper member; one of said magnetic tumblers having a portion thereof normally extending into said smaller keeper plate opening, a second of said magnetic tumblers having a portion thereof normally extending into said larger keeper plate opening and a third of said magnetic tumblers having a portion thereof normally extending into another of said keeper plate openings; means defining a first slot in said lock for receiving a program member having a magnetic portion adapted to move said third tumbler out of its associated keeper plate opening; means defining another slot in said lock for receiving a pass card having one or more magnetic portions adapted to move said first tumbler or said first and second tumblers out of their associated keeper plate openings; and means for creating limited relative movement between said tumbler-carrying member and said keeper member when said first tumbler is moved out of its smaller keeper plate opening, and for creating extended relative movement between said tumbler-carrying member and said keeper member when said second tumbler is moved out of its larger keeper plate opening.

26. A magnetic lock according to claim 25, and further comprising control circuit means for actuating operator means; said control circuit means comprising first switch means operable in response to limited relative movement between said tumbler-carrying member and said keeper member; control switch means for selectively rendering actuation of said first switch means effective to actuate operator means; and second switch means operable in response to extended relative movement between said members for actuating operator means.

27. A magnetic lock according to claim 25, wherein each of said magnetic tumblers is an elongated, generally cylindrical member magnetically polarized along its length.

28. A magnetic lock according to claim 25, wherein said tumbler-carrying member is disposed above said keeper member and said tumblers are normally maintained in their said locking positions by gravity.

29. A magnetic lock according to claim 25, wherein said tumbler-carrying member is movable relative to said keeper member, and further comprising a tamperprevention member slidably disposed in said tumblercarrying member, and fixed means disposed above and adjacent to said tamper-prevention member; whereby when said tumblers are moved upwardly out,of their locking positions by a non-magnetic force said tamperprevention member will be moved upwardly and will engage said fixed means when said tumbler-carrying member is moved rearwardly, thereby preventing substantial movement of said tumbler-carrying member.

30. A magnetic lock comprising: first and second switch means; a movable member; key-operable means for selectively moving said movable member; actuator means for actuating said first switch means in response to limited movement of said movable member and for actuating said second switch means in response to extend movement of said movable member; a plurality of magnetically responsive tumblers normally biased into locking positions for preventing substantial movement of said movable member; at least one of said magnetically responsive tumbler means being movable out of its said locking position in response to the insertion of a magnetically coded program member into said lock; at least one other of said tumblers being movable out of its said locking position in response to the insertion of a first type of key into said lock for permitting limited movement of said movable member; and at least one other of said magnetically responsive tumblers being movable out of its said locking position in response to the insertion of a second type of key into said lock for permitting extended movement of said movable member. 

1. A magnetic lock comprising: a tumbler-carrying member and a keeper member disposed adjacent to one another with one of said members being disposed below the other of said members; means defining a key-receiving opening below the lower of said tumblercarrying member and said keeper member; at least two magnetically responsive tumblers movably disposed in said tumbler-carrying member; first abutment means carried by said keeper member for engaging a portion of one of said tumblers to prevent substantial relative movement between said tumbler-carrying member and said keeper member; second abutment means carried by said keeper member for engaging a portion of the other of said tumblers to prevent extended relative movement between said tumbler-carrying member and said keeper member; said one tumbler being normally biased into a locking position wherein it engages said first abutment means on said keeper member when relative movement between said tumbler-carrying member and said keeper member is created; said other tumbler being normally biased into a locking position wherein it engages said second abutment means on said keeper member when relative movement between said tumblercarrying member and said keeper member is created; each of said tumblers being movable out of its said locking position by the magnetic field set up between said tumbler and a magnetically responsive portion of a key inserted into said key-receiving opening; means for creating limited relative movement between said tumbler-carrying member and said keeper member when said one tumbler is out of its said locking position and said other tumbler is in its said locking position and for creating extended relative movement between said members when both of said tumblers are out of their said locking positions.
 2. A magnetic lock according to claim 1, and further comprising control circuit means for actuating operator means; said control circuit means comprising first switch means operable in response to limited relative movement between said tumbler-carrying member and said keeper member; control switch means for selectively rendering actuation of said first switch means effectiVe to actuate operator means; and second switch means operable in response to extended relative movement between said members for actuating operator means.
 3. A magnetic lock according to claim 1, and further comprising a third magnetically responsive tumbler movably disposed in said tumbler-carrying member; third abutment means carried by said keeper member for engaging a portion of said third tumbler; said third tumbler being normally biased into a locking position wherein it engages said third abutment means; and means defining a program member receiving opening in said lock for receiving a program member having a magnetically responsive portion adapted to move said third tumbler out of its said locking position.
 4. A magnetic lock according to claim 1, and further comprising spring means normally maintaining said tumbler carrying member and said keeper member in a locking position, relative to one another, wherein each of said tumblers is disposed in its said locking position.
 5. A magnetic lock according to claim 1, and further comprising a tamper-prevention member operative in response to a non-magnetic force moving said tumblers out of their said locking positions to prevent substantial relative movement between said tumbler-carrying member and said keeper member.
 6. A magnetic lock according to claim 1, wherein said tumbler member and said keeper member are generally planar members disposed adjacent to one another, and each of said magnetically responsive tumblers is a generally elongated, cylindrical member slidably disposed in said tumbler carrying member for movement in a direction generally along the axis of the tumbler; and further comprising a plurality of openings in said keeper member; each of said openings being adapted to receive the end portion of one of said cylindrical tumblers; one of said openings in said keeper member being larger than the other of said openings; said first abutment means comprising a portion of the peripheral edge of said smaller opening in said keeper member and said second abutment means comprising a portion of the peripheral edge of said larger opening in said keeper member.
 7. A magnetic lock according to claim 6, wherein each of said generally cylindrical tumbler members is magnetically polarized along its length.
 8. A magnetic lock according to claim 6, wherein said key-receiving opening comprises means defining a card-receiving slot having a forward end into which a card-shaped key is adapted to be inserted, and an open rear end; and wherein said means for creating movement between said tumbler-carrying member and said keeper member comprises flange means connected to one of said tumbler-carrying member of said keeper member; said flange means overlying said open rear end of said key-receiving slot and being adapted to be engaged by a card-shaped key inserted into said slot.
 9. A magnetic lock according to claim 6, wherein said tumbler-carrying member is disposed above said keeper member, and said tumblers are normally maintained in their said locking positions by gravity.
 10. A magnetic lock according to claim 9, wherein said tumbler-carrying member is movable relative to said keeper member, and said flange means comprises a flange connected to said tumbler member; and further comprising first and second switch means and actuator means carried by said tumbler member for sequentially actuating said first and second switch means as said tumbler member is moved rearwardly relative to said keeper member.
 11. A magnetic lock according to claim 6, wherein said tumbler-carrying member is movable relative to said keeper member, and further comprising spring means normally biasing said tumbler member to a retracted position wherein each of said magnetically responsive tumblers has one of its ends disposed in one of said keeper member openings.
 12. A magnetic lock according to claim 6, wherein said tumbler-carrying member is movable relative to said keeper member, and further comprising a non-magnetic tampEr-prevention member slidably disposed in said tumbler-carrying member, and fixed means disposed above and adjacent to said tamper-prevention member; whereby when said tumblers are moved upwardly out of their locking positions by a non-magnetic force said tamper-prevention member will be moved upwardly and will engage said fixed means when said tumbler-carrying member is moved rearwardly, thereby preventing substantial rearward movement of said tumbler-carrying member.
 13. A magnetic lock comprising: a tumbler-carrying member; a keeper member disposed adjacent to said tumbler-carrying member; means defining a key-receiving opening in said lock; at least two magnetized tumblers movably disposed in said tumbler-carrying member; first abutment means carried by said keeper member for engaging a portion of one of said tumblers to prevent substantial relative movement between said tumbler-carrying member and said keeper member; second abutment means carried by said keeper member for engaging a portion of the other of said tumblers to prevent extended relative movement between said tumbler-carrying member and said keeper member; said one tumbler being normally biased into a locking position wherein it engages said first abutment means on said keeper member when relative movement between said tumbler-carrying member and said keeper member is created; said other tumbler being normally biased into a locking position wherein it engages said second abutment means on said keeper member when relative movement between said tumbler-carrying member and said keeper member is created; each of said tumblers being movable out of its said locking position by the magnetic field set up between said tumbler and a magnetized portion of a magneticallycoded key member inserted into said key-receiving opening; means for creating limited relative movement between said tumbler-carrying member and said keeper member when said one tumbler is out of its said locking position and said other tumbler is in its said locking position and for creating extended relative movement between said members when both of said tumblers are out of their said locking positions.
 14. A magnetic lock according to claim 13, and further comprising control circuit means for actuating operator means; said control circuit means comprising first switch means operable in response to limited relative movement between said tumbler-carrying member and said keeper member; control switch means for selectively rendering actuation of said first switch means effective to actuate operator means; and second switch means operable in response to extended relative movement between said members for actuating operator means.
 15. A magnetic lock according to claim 13, and further comprising a third magnetized tumbler movably disposed in said tumbler-carrying member; third abutment means carried by said keeper member for engaging a portion of said third tumbler; said third tumbler being normally biased into a locking position wherein it engages said third abutment means; and means defining a program member receiving opening in said lock for receiving a program member having a magnetically responsive portion adapted to move said third tumbler out of its said locking position.
 16. A magnetic lock according to claim 13, and further comprising spring means normally maintaining said tumbler-carrying member and said keeper member in a locking position, relative to one another, wherein each of said tumblers is disposed in its said locking position.
 17. A magnetic lock according to claim 13, and further comprising a tamper-prevention member operative in response to a non-magnetic force moving said tumblers out of their said locking positions to prevent substantial relative movement between said tumbler-carrying member and said keeper member.
 18. A magnetic lock according to claim 13, wherein said tumbler member and said keeper member are generally planar members disposed adjacent to one another, and each of said magnetically responsive tumblerS is a generally elongated, cylindrical member slidably disposed in said tumbler carrying member for movement in a direction generally along the axis of the tumbler; and further comprising a plurality of openings in said keeper member; each of said openings being adapted to receive the end portion of one of said cylindrical tumblers; one of said openings in said keeper member being larger than the other of said openings; said first abutment means comprising a portion of the peripheral edge of said smaller opening in said keeper member and said second abutment means comprising a portion of the peripheral edge of said larger opening in said keeper member.
 19. A magnetic lock according to claim 18, wherein each of said generally cylindrical tumbler members is magnetically polarized along its length.
 20. A magnetic lock according to claim 18, wherein said key-receiving opening comprises means defining a card-receiving slot having a forward end into which a card-shaped key is adapted to be inserted, and an open rear end; and wherein said means for creating movement between said tumbler-carrying member and said keeper member comprises flange means connected to one of said tumbler-carrying member or said keeper member; said flange means overlying said open rear end of said key-receiving slot and being adapted to be engaged by a card-shaped key inserted into said slot.
 21. A magnetic lock according to claim 18, wherein said tumbler-carrying member is disposed above said keeper member, and said tumblers are normally maintained in their said locking positions by gravity.
 22. A magnetic lock according to claim 21, wherein said tumbler-carrying member is movable relative to said keeper member, and said flange means comprises a flange connected to said tumbler-carrying member; and further comprising first and second switch means and actuator means carried by said tumbler-carrying member for sequentially actuating said first and second switch means as said tumbler-carrying member is moved rearwardly relative to said keeper member.
 23. A magnetic lock according to claim 18, wherein said tumbler-carrying member is movable relative to said keeper member, and further comprising spring means normally biasing said tumbler-carrying member to a retracted position wherein each of said magnetically responsive tumblers has one of its ends disposed in one of said keeper member openings.
 24. A magnetic lock according to claim 18, wherein said tumbler-carrying member is movable relative to said keeper member, and further comprising a tamper-prevention member slidably disposed in said tumbler-carrying member, and fixed means disposed above and adjacent to said tamper-prevention member; whereby when said tumblers are moved upwardly out of their locking positions by a non-magnetic force said tamper-prevention member will be moved upwardly and will engage said fixed means when said tumbler-carrying member is moved rearwardly, thereby preventing substantial rearward movement of said tumbler-carrying member.
 25. A magnetic lock comprising: a generally planar tumbler-carrying member having a plurality of magnetic tumblers slidably mounted therein for transverse movement across the thickness of said member; a generally planar keeper member disposed adjacent to and substantially parallel to said tumbler carrying member; means defining a plurality of openings in said keeper member for receiving portions of said tumblers to prevent or limit relative sliding movement between said tumbler-carrying member and said keeper member; said openings in said keeper member including at least one smaller opening adapted to receive a portion of one of said magnetic tumblers in said tumbler-carrying member to prevent substantial relative movement between said tumbler-carrying member sand said keeper member, and at least one larger opening adapted to receive a portion of the other of said magnetic tumblers to prevent extended relative movement between said tumbler carrying member and said keeper member; one of said magnetic tumblers having a portion thereof normally extending into said smaller keeper plate opening, a second of said magnetic tumblers having a portion thereof normally extending into said larger keeper plate opening and a third of said magnetic tumblers having a portion thereof normally extending into another of said keeper plate openings; means defining a first slot in said lock for receiving a program member having a magnetic portion adapted to move said third tumbler out of its associated keeper plate opening; means defining another slot in said lock for receiving a pass card having one or more magnetic portions adapted to move said first tumbler or said first and second tumblers out of their associated keeper plate openings; and means for creating limited relative movement between said tumbler-carrying member and said keeper member when said first tumbler is moved out of its smaller keeper plate opening, and for creating extended relative movement between said tumbler-carrying member and said keeper member when said second tumbler is moved out of its larger keeper plate opening.
 26. A magnetic lock according to claim 25, and further comprising control circuit means for actuating operator means; said control circuit means comprising first switch means operable in response to limited relative movement between said tumbler-carrying member and said keeper member; control switch means for selectively rendering actuation of said first switch means effective to actuate operator means; and second switch means operable in response to extended relative movement between said members for actuating operator means.
 27. A magnetic lock according to claim 25, wherein each of said magnetic tumblers is an elongated, generally cylindrical member magnetically polarized along its length.
 28. A magnetic lock according to claim 25, wherein said tumbler-carrying member is disposed above said keeper member and said tumblers are normally maintained in their said locking positions by gravity.
 29. A magnetic lock according to claim 25, wherein said tumbler-carrying member is movable relative to said keeper member, and further comprising a tamper-prevention member slidably disposed in said tumbler-carrying member, and fixed means disposed above and adjacent to said tamper-prevention member; whereby when said tumblers are moved upwardly out of their locking positions by a non-magnetic force said tamper-prevention member will be moved upwardly and will engage said fixed means when said tumbler-carrying member is moved rearwardly, thereby preventing substantial movement of said tumbler-carrying member.
 30. A magnetic lock comprising: first and second switch means; a movable member; key-operable means for selectively moving said movable member; actuator means for actuating said first switch means in response to limited movement of said movable member and for actuating said second switch means in response to extend movement of said movable member; a plurality of magnetically responsive tumblers normally biased into locking positions for preventing substantial movement of said movable member; at least one of said magnetically responsive tumbler means being movable out of its said locking position in response to the insertion of a magnetically coded program member into said lock; at least one other of said tumblers being movable out of its said locking position in response to the insertion of a first type of key into said lock for permitting limited movement of said movable member; and at least one other of said magnetically responsive tumblers being movable out of its said locking position in response to the insertion of a second type of key into said lock for permitting extended movement of said movable member. 